The major talking point after Chelsea’s 1-0 victory over Manchester United on Sunday is whether David Luiz should be condemned for going to ground and smiling after getting hacked to the ground by Rafael da Silva.

The incident occurred in the 87th minute just after Juan Mata had given the Blues a 1-0 lead. Luiz had the ball near the corner flag and Rafael was applying tight pressure. As Luiz shielded the ball the United defender forced him closer to the corner flag before sweeping his right leg through the Chelsea man, dumping him out. Luiz went down in a heap but flashed a smile to the Chelsea faithful as he lay on the ground. Referee Howard Webb then proceeded to show Rafael a straight red card.

The incident compelled Sir Alex Ferguson to go off on Luiz in his post match comments. “The ref has been bought by the fact Luiz is rolling about,” Ferguson said.

Later in his tirade the United manager continued, “[Luiz] was smiling. It’s bad. What kind of professional is that?

“I wouldn’t say it was violent conduct. The referee hasn’t even seen it, I don’t think he could see it at all. But he has gone with the fact that Luiz has rolled about on the floor and I think that convinced him it was a red card.”

So the question must be asked : Did Luiz cross an unwritten line of footballing morality by going to ground and smiling?

Those who believe that Luiz didn’t cross the line will argue that Rafael hacked down the bushy-haired Brazilian. There was nothing light about the tackle. It was an old fashioned scythe-job that, on another day, could have broken a player’s leg.

Luiz supporters would also note that Ferguson’s claim that the tackle wasn’t violent is hogwash. If the roles were reversed and it was Luiz laying the blow on Rafael, the Scot would have been shouting for a multiple game suspension. There was clear intent by Rafael to take Luiz down, your classic corner-flag foul from a team scrambling to get back into a game.

In other words, Luiz’ smile wasn’t because he was faking the foul, it was because he was expecting it. By smiling the Chelsea defender, who is well known as a light-hearted prankster and fan favorite, was doing nothing more than assuring the Chelsea faithful that he was OK.

Those who think Luiz crossed the line will see things differently.

They’ll argue that while it may have been a foul, the manner in which Luiz hit the deck – curling up and writhing in pain – was overly dramatic and unprofessional. It was the move of an actor looking for applause from his audience, something that has no place in football.

Critics will also note that the fall, combined with the huge smile, is a tacit acknowledgement that the challenge wasn’t nearly as bad as it looked and that Luiz was effectively revelling in his role in Rafael’s red card.